Ferroelectric system

Burrows AD (2004) Crystal Engineering Using Multiple Hydrogen Bonds 108 55-96 Bussmann-Holder A, Dalai NS (2007) Order/Disorder Versus or with Displacive Dynamics in Ferroelectric Systems. 124 1-21... 

Order/Disorder Versus or with Displadve Dynamics in Ferroelectric Systems... 

Therefore we propose here an alternative route to inspect the local dielectric and polarization properties using non-destructive and non-invasive methods based on scanning force microscopy (sfm). Simultaneously, these techniques offer a high resolution in real space being extended down to the atomic scale when inspecting ferroelectric systems under ultra-high... 

Ferroelectrics of interest are often multicomponent oxides. The metal elements in concern do not always show enough solubility in given solvent. Therefore, the choice of precursor compounds and the dissolution procedures, as well as their behaviors toward moisture and heat, are all important aspects to consider. We select a few representative ferroelectric systems to illustrate the practices reported on the solution preparations. 

Other reported ferroelectric systems include PbTi03 [39], BaTiOa [18], and PMN-PT [30]. Solution preparation for these systems is similar to the procedures already discussed. The reader should easily find precursors and appropriate procedures according to these examples. 

When single-crystal substrates with a small lattice mismatch are used, sol-gel produces epitaxial films for a few ferroelectric systems. Although epitaxial growth of crystalline films from an amorphous layer has been observed in the amorphous silicon to silicon transformation, sol-gel epitaxy only began to emerge as a possible fabrication technique in the last few years. Hirano and Kato were the first to observe the epitaxial growth of LiNbOs on the sapphire (110) face [37]. Xu et al. [34,43] found the epitaxial growth of LiNbOs on the LiTaOs (110) face and the LiNbOa (006) face. Epitaxial KNbOs was reported... 

This scheme was originally derived for brain waves, and extended by taking into account a possible short-range interaction between excited enzymes, which then tends to organize them into a ferroelectric system. This results in an extension of Eqs. (19) and (20) into a complicated set of equations whose solutions are limit cycles this means that the system will then tend to oscillate with a fixed amplitude. 

As the polarization is not confined to a fixed direction in a monoclinic phase, its unconstrained rotation can explain the highly valued properties of ferroelectric systems near the MPB [25]. A relationship between the polarization rotation and a strong enhancement of the electromechanical response in perovskite ferroelectrics was demonstrated by Fu and Cohen [32], from a first principles study of the internal... 

Figure 18.15 Application of the model of hardening-softening transitions to the case of an aged and quenched state of a ferroelectric system with alternating distribution of charged defects, (a) Domain wall free energy versus...

The antiferroelectric phase, discovered in 1989, is currently the snbject of mnch research because of the great potential in display devices. The application of an electric field to an antiferroelectric material indnces a ferroelectric ordering which can be switched in the usnal way by a reversed pnlse. Removal of the field will regenerate the antiferroelectric phase. Such a system has the advantage over the normal ferroelectric system of well-defined electric field thresholds and accordingly shonld be mnch easier to multiplex. 

Recently, ferroelectric properties have been found in chiral columnar systems [27] and also discoid cholesteric and discoid-blue phases have been found [17]. H. Bock describes chiral ferroelectric systems in Chapter 10. 

Typical property of a ferroelectric system, the hysteresis loop, shows marked dependence on the pressure (Fig. 29). Observations of the hysteresis loops have shown that the spontaneous polarization abruptly increases at the Sm A-Sm C transition point when T decreases at p = const (Fig. 30a) or when p increases at T = const (Fig. 30b). That is accompanied by an increase of the tilt angle (Fig. 30c). 

In the search for novel materials, particularly new ferroelectric materials, new phase types were also discovered, notably the antiferroelectric phase [56] which, with tristable switching characteristics, also has potential for display use, possibly overcoming some of the difficulties with ferroelectric systems and providing a further display device of high quality. 

---